In general, only 0.0086% of all the earth's water volume may be used. When considering disasters due to climate change in mind, water may not be available enough.
Water is very important to human life and is used variously as water for living or industrial water. Water may be contaminated with heavy metals, nitrate, fluoride, etc., due to industrial development and it is very harmful to health to drink contaminated water.
Recently, deionization technologies for purifying contaminated water and sea water for use as agricultural, industrial, or irrigation water have been variously studied.
These deionization technologies are techniques for deionization or deionization of water by removing various suspended solids or ion components contained in the sea water or polluted water such as waste water, and may employ an evaporation method to evaporate water by using a heat source such as fossil fuels or electric power, a filtration method to filter and remove foreign materials by using a separation membrane, or an electrodialysis method to remove ions by using an electrolytic action of an electrode cell.
The evaporation method evaporates moisture by using fossil fuels or electricity as a heat source, is inefficient due to the large volume of the deionization equipment, increases the manufacturing cost due to an increase in the consumption of energy, and causes contamination of air due to the use of fossil fuels.
The filtration method removes foreign matters by applying a high pressure to a separator and thus the cost of energy increases.
The electrodialysis method has to constantly replace an electrode cell with another, and does not only generate a waste factor due to the replacement of the electrode cell but also has the disadvantage of increasing human and material incidental expenses in accordance with the replacement of the electrode cell.
Korean Patent Registration Publication No. 501417 discloses a waste water deionization apparatus using a reverse osmosis membrane method/electrode method, the waste water deionization apparatus comprising: a reverse osmosis membrane device to primarily remove salt components from water to be treated in which the water to be treated is introduced with a predetermined pressure into the reverse osmosis membrane device; a deionization electrode device that secondarily removes salt components from the water that has been primarily processed in the reverse osmosis membrane device in which a spacer, a positive electrode and a negative electrode are sequentially provided in a cylindrical tank; an energy recovery device for utilizing a brine-side pressure of the reverse osmosis membrane device for use to pressurize inlet water of the deionization electrode device; a power supply device for supplying power to the positive electrode and the negative electrode provided in the deionization electrode device; and a controller for controlling valves provided in pipes through which the water to be process in order to perform a deionization process for deionizing the water to be treated in which the water to be treated is introduced into the deionization electrode device, and a reproduction process for desorbing ions adsorbed to the electrode during the deionization process. However, such a waste water deionization apparatus includes the reverse osmosis membrane device and the deionization electrode device individually and thus may cause the large size of the deionization apparatus and require a lot of manufacturing cost.
Thus, the present inventors have consistently proceeded a study on a technique of slimming a deionization apparatus and reducing a production cost, to thus invent and derive structural features capable of deionizing only particular ions from water to be treated, while having a high storage capacitance, to thereby have completed the present invention that is more economical, and possibly utilizable, and competitive.